6. A serial console can be connected through UART1 CN853. I already soldered another plug on top of the original one. Pinout see below. You'll need a level shifter LVTTL-to-RS232 as well in order to connect a PC serial port.

Firmware

Though the CP1 was available in the US and UK, there seems to be no english firmware for download available.
Two japanese firmware images are available. You can flash them by just placing the .IMG file in a sub-folder called 'Update'.

Remote Access

Since firmware Ver.2.00 a web server is set up - however in japanese. Initial login is

ユーザー名 (loginname): root
パスワード (password): password

The web server allows you to configure your account data more easily than with the remote control.
Unfortunately this login and password is not working on the serial console. With a root access account one might be able to add english translations.

No other services seems to run as all ports are closed.

Hardware Disassembly

1. To open the nice housing, you first have to remove two white square shaped sticker on the lower back side.
The screws fix two white bushings, which have to be taken out in order to seperate the acrylic glass base.

remove sticker to open cover

2. Next you have to remove a rectangular white sticker. which is used as a diffusor for the blue led.

slightly shift display in arrow direction

3. To seperate the cover, you have to move carefully the display towards the direction marked with red arrows. The ribbon cable is on the bottom side, so you can open the housing now.

next remove 6 screws to open shield

4. The PCBs are shielded with a blank sheet fixed with six screws. For those you need well fitting screw driver, because the four ones marked in red are tightend very hard. I had to drill them out !

mainboard with display connector

5. Front display is connected to ribbon connector (red square). Another pwr button is inside (blue marking), next to it a reset button (green marking).

UART1 serial connector

6. A serial console can be connected through UART1 CN853. I already soldered another plug on top of the original one. Pinout see below. You'll need a level shifter LVTTL-to-RS232 as well in order to connect a PC serial port.